Protecting-shield for furnace-flues.



H. W. LASH. PROTECTING SHIELD FOR FURNACE FLUES.

AFPLIOATION FILED BBPTJ'T, 1907.

Patented July 13,1909.

2 SHEETS-SHEET 1.

H. W. LASH.

PROTEGTING SHIELD FOR FURNACE PLUES.

APPLICATION FILE-I) SEPT.27, 1907.

2 SHEETS-SHEET 2.

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$6M yww. QC

UNITED STATES PATENT OFFICE.

HORACE W. LASH, OF CLEVELAND, OHIO,'1\SSIGNOR TO THE GARRETT-CROIHVELL ENGINEERING COMPANY, OF CLEVELAND, OHIO, A CORPORATION OF OHIO.

PROTECTING-SHIELD FOR FURNACE-FLUES.

To all whom it may concern: Y

, Be it known that I, HORACE W. LASH, a citizen of the. United States, residing at Cleveland, .in the county of Cuyahoga and State of Ohio, have invented a certain new and useful Improvement in Protectin Shields for Furnace-Flues, of which the f lowing is a full, clear, and exact description. The present invention relates to the shielding of ambs and arches of the ports of the fines leading from furnac es to the regenerators, against the action of the hot out-flowing currents of burned gas. p 1

The invention is more particularly tobe characterized as .relating to' a structure whereby the burned gases are prevented from striking the faces of the aforesaid arches and their supporting jambs at a high temperature, and thus preserving the structure from disintegration as distinguished from those prior devices known in the art,

including meansfor artificially cooling the interior or rear portion of the arch, while the burned gases, at high temperature, play freely on the face thereof.

tice last referred to, namely, the simple practics of backing up the brick work or inserting therein artificial cooling means, such as water pipes, is old and commonly used wherever the engineer thinks the cost and risk are compensated by the wear saved. I donot, therefore, desire to be understood as regarding this idea broadly, of artificially cooling the arches, as patentable, since not only is this within the obvious province of every engineer, but also because I do not use an arrangement which can, in truth, be said to artificially cool the arches, as the novel arrangement which I have provided does not operate in this manner but, instead, serves as a protecting shield in front "of the arch,

rotecting it from the impingement of the liurned gases and cooling the gas current in immediate proximity to the face of the arch,

below the-temperature at which the brick work becomes friable or fusible under the influence of such gases, the 'ainbs or supports of the arch being similarly protected In order that my invention may be better understood, reference is had to the following specification, ,and the accompanying drawings, in which-- Figurel is a cross section of a furnace.

Specification of Letters Patent.

Application filed September 27, 1907. Serial No. 394,932.

Patented July 13, 1909.

the air-flue being above .the gas flue'with a separatuw wall or arch C, therebetween. The

upper wall A of the air flue is inclined downward toward the outlet so as to direct the incoming flow of the air, and consequently the mixture of air and gas, properly on to the hearth of the furnace and also to pre .vent'the flame, created by the burning mixture, from striking against the furnace roof and'fusing it away. There are two sets of these gas lines used .with regenerative furnaces, as is well known, one set serving as the outlet, while the other serves as the inlet for the flow of the various gases, the direction of flow being reversed from time to time.

There is no wear upon the transverse partition wall or arch C se )arating the gas and air flues, or of the jam s ,C supporting this partition, due to the flowing of the unburned gas and air thereby into the furnace, but the gaseous products of combustion passing out of the furnace at a high temperature fuse and wear away the nose C of this partition and necessitate the renewal thereof from time to time in order to avoid an undesirable change in the direction of the inllowing current when the same ports are used as inlets instead of outlets. I

I am aware that it has been proposed to follow the usual expedient of iron and steel engineering practice and artificially cool the partitions against which the outgoing gases play. This, of course, retards the wearing action to considerable extent, but is based upon the wrong principle, as it is remedial or counter-active in its theory rather than preventive.

It is not thoroughly effective to, more or less remotely, backup the nose with cooling means when the burned gases are permitted to play upon the outside of the same at a high temperature, since the face of the bricks will be found to eventually rise to the high temperattireand will gradually fuse or crum ble away,- according .to the nature of thebrickemployed, and the nose will thus gradwally. Wear back or down toward the artificial cooling means. 1 I For the reasonsabove noted, 'I do not em-- ploy the method. of artificially coolingthe v 'partition'therebetween, means located} 111 front aof-the said partition and betweenthe arch or partition for the purpose of'preservmg the same, but ,I place in front of the face of [the arch, againstwhich the hot gases play, a protectingshield, preferably made up of water cooled i es D, though it' is obnone that this shie ld may have other conetruction Withinthe limits of economy. I la prefer to extend the'shield to pra'eticall the upper and lower edges of the arch, an also to protect jamb. C supporting the arch or;

partition in like manner, as it is found that the said edges'areworn away-under the action of the highlyheated products of-combustion impinging thereon. By the em 'loyment of this shield, the facesof the arc and its supporting .wallsare protectedagainst the,

impingementof the outflovving gases, and the gaseous products of combustionin immediate proximity to. the faces arefeooled be-' lowthe temperature at which'th'ey fuse the bricks ,or cause. them 'to.'. crumble'; and .thus the arch. wears so well andfso long that" it is POrtingmeans therefor in order to sustain-it against the disintegrating effect of the outflowing currents. The advantagejof'this ar "rangementwill be-obvious' to thosefamiliar with the effect" of highlly' heated products of' combustion upon bri'c the latter is backed up by artificial cooling I-meansof some sort, since in my structure the.

-. fade of thebricks'at the portion of the'ar'ch,

:4'0 where the Wear are place is protectedagainst' the impingement of the burned gases and does not-readily reach the crumbling or fusing temperature, and is,- therefore maintaine'd in better condition than could be had.

145' otherwise; H

Obviously certain modifications could be -made in the shield which I employ, but the general features of the arrangement may be said broadly to require that theprotecting shield be" placed soias to prevent the outtion.

unnecessary to employ any; additional sup-- work, even where flowing pro-ducts' of combustion from 'impmging against the face of the arch, at such I a temperature as to destroy the arch. I

Having thus described my lnv'ention, I claim:

products of combustion befdrethe latter strike against the face of'the said'partltion.

V 2. In a. furnace of the-class descr bedhair- 4 ing gas and air flue ports with a transverse; .55

partition: therebetween, means to cool the outflowing products of combustion before the hitter strike againstthe face of. said par-v -1. In a furnace ofithe classdescribed ha'v-.

tition,".'and-means for cooling the products" of cbmbustio'n before the latter strikejagainst thev fac'e of the jamb supporting said parti 3.. In afurnaceof'the,clfass desei ihed'havoc'ated betweenthega's and air flue ports and-infrorit 'o'f said-partition andiextended. ,substantially to the edges aof; said-partition..-

'4; In a furnace ofthe' class descnbed having gas and air flue ports one above the other with, a separating partition or arch therebetween, a water cooled shieldlocated be- .tweenthe' gasand air flue ports and infront ofsaid arch, protecting the face'of .thelatter from. the impingement of outflow products of combustion.

5.. In a furnace of the class describedhaving gas andair flue ports one above the other artition-.therebetvfieemaa gasicoolingshieldj v With. a separating partition or arch there-.

between, 'se arate water cooled pipes in front of em arch and the walls supporting saidarch, protecting the faces of said arch and walls from the impingement'of the outflowing products of combustion.

In testimony whereof, I hereunto afiix my signature in; the presence .of two witnesses.

v [HQRA W. LAsI-r.

Nitnesses'f I Y R. SULLIVAN,

' E. B. GILOHRIST. 

